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Work more economically with modular pumps

Reliably extract raw materials for soap production

For the production of soaps, different basic materials have to be provided for automatic further processing, depending on the recipe. The palette ranges from light-bodied oils or perfume bases to semi-solid fats and colour suspensions to tough waxes. After production, the sometimes corrosive and abrasive residues have to be disposed of. Modular and robust drum and air-operated diaphragm pumps are suitable for all these applications, because they gently and reliably convey a wide variety of media.

Today, the vast majority of soap variations are produced according to special recipes from many individual components. This begins with the selection of raw materials for the actual saponification process and continues with additives such as care substances, colouring pastes or waxes and even perfume components. All components have different properties in terms of viscosity, chemical characteristics or flash point. Nevertheless, they have to be reliably and safely fed into the automatic production from the delivery containers. The Kappus Group, a traditional company founded in 1848, produces 20,000 tonnes of basic soap annually. For this purpose, the company relies on proven delivery pumps from Flux for the production of solid soap at its Heitersheim site, because the modular design of pump and drive always allows the right pump configuration to be configured for the respective medium.

Flexible pumps promote raw material diversity
Modern soap production works largely automatically and mixes the individual components to the desired starting product according to the specifications. For this purpose, the raw materials and additives delivered in different containers have to be transferred to the production tanks. Despite the variety of substances, only three different pump models are used at the Heitersheim soap manufacturer. Ulrich Kneip, head of technology at Kappus, explains why: "Two barrel pumps of the type F 430 S and FP 42 4S and an air-operated diaphragm pump FDM 25 S/ TT made of stainless steel provide us with the necessary bandwidth for all the substances used in production and thus drastically reduce the effort for spare parts storage, operating instructions and reserve pumps. Thanks to the modular design of the actual pump and the drive motor, we can also change parts quickly if necessary. For example, a normal drive can be quickly exchanged for an explosion-proof model if necessary, or a more powerful motor for highly viscous fluids can be used to achieve the desired flow rate. In addition to the easy motor exchange, the quick disassembly for cleaning is also an advantage that should not be underestimated, in order to react flexibly to changing product components".

Sophisticated pump technology
The modular system offers pump drives ranging from simple commutator motors to brushless motors for practically wear-free continuous operation to three-phase geared motors or a compressed-air drive. On request, the motors can also be supplied with speed adjustment, e.g. in order to infinitely regulate flow rates at any time. All drives are placed on top of the shaft of the drive shaft in the two pumping stations and tightened with only one nut. This makes them easy and quick to change. Depending on the pump model, medium and drive, up to 220 l/min at a pressure of up to approx. 26 mWS (approx. 2.6 bar) can be delivered with the electric drives. The air motor achieves delivery rates of approx. 240 l/min at 30 mWS (approx. 3 bar). The suction geometry of the FP 425 model is designed for low residual volume and allows e.g. drums to be emptied by more than 99 %, i.e. almost completely. For soap production, two pump models in particular have proven their worth: the F 430 S model with a mechanical seal towards the drive shaft and the sealless version type FP 424 S with a specially designed shaft guide. All pumps used at Kappus in soap production are made of stainless steel with a special length of 1,500 mm (standard length is 1,200 mm for IBCs), so that they can be used universally. If required, materials such as polypropylene, polyvinylidene fluoride are also used, e.g. for special corrosive or caustic media.

Long service life
In both pumps, the outer delivery tube encloses the inner guide tube for the drive shaft. A good, smooth-running bearing of the drive shaft is important for the pump function. Here, the pump specialists use two different approaches, depending on the medium: In the model with a mechanical seal, this seals the guide tube with the shaft at the bottom, directly on the pump, against penetrating medium. The shaft itself is supported and guided in several plain bearings inserted in the inner tube. This also allows, for example, the pumping of wax that has been heated up to 85 °C to reduce its viscosity. In contrast, the sealless model works with a spiral-shaped guide bearing in the inner tube, located approximately in the middle of the shaft. During operation, this conveys penetrating medium back into the open, similar to an Archimedean screw. This makes this design particularly suitable for low-viscosity, even aggressive and fast-flowing fluids that neither harden nor crystallise. The design prevents unwanted deposits inside and thus extends the pump's service life enormously. Both pump models can be easily disassembled into their individual components for easy cleaning.

Diaphragm pump takes over disposal
For the treatment of lye, on the other hand, other pump characteristics are required. Therefore, a robust air-operated diaphragm pump in stainless steel design with up to 178 l/min at 8 bar delivery pressure is used here. It pumps the waste liquor from the collection sump into an intermediate tank for processing. Since the pump can handle even abrasive particles without any problems, it is ideally suited for waste disposal. The dry-running safe pump is dry self-priming and even flooding does not bother it. Its oil-free operation allows it to be used not only in soap production, but also in the pharmaceutical and food industries, as well as in applications with waste water, slurry, chlorine bleach, cleaning agents, etc. The pump can also be used in the food industry. Chlorine bleach, cleaning agents, etc. Depending on the application, the pump is made of aluminium, stainless steel, PP or polyvinylidene fluoride. Despite the variety of substances to be pumped in soap production, only three universally applicable pumps and a few motor models are sufficient for production pumping. The modular design allows the systems to be systems in such a way that the finished pump is always suitable for the material to be pumped. Maintenance costs, spare parts stocks and, last but not least, administrative costs, e.g. for the necessary operating instructions, are reduced to a minimum.


In 1950 the worldwide’s first electrical drum pump was named FLUX. Meanwhile the undisputed pioneer on the field of drum pump technology also has outstanding expertise and experience in many other areas of pump technology. The comprehensive product portfolio ranges now from various pump types with motors, flow meters and accessories to subsystems for the plant engineering and special system solutions like the drum emptying systems. The internationally acting family company with its 7 subsidiaries and numerous sales partners supplies its products to more than 100 countries worldwide.

Contact and information:

Talweg 12
D-75433 Maulbronn 
Phone +49 (0)7043 / 101-0
Fax +49 (0)7043 / 101-111

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